I think the most important factor here is not who did or didn’t do what or who was operating the aircraft. The fact is that Airbus designed this cowling latching system which quite plainly:
1. Could cause catastrophic damage to an airliner
2. appears to be not suitable for purpose judging by the number of recorded incidents and now highlighted by this major one because it’s BA
Once established that the design was not good enough a redesign should have been demanded rather than placing the responsibility on humans always doing the right thing which they are never always going to do.
I think this is as serious as the DC10 cargo door. If someone doesn’t check that the cowls are locked and they’re not then the a/c and its pax and crew are in serious jeopardy.
It is perfectly obvious that this could happen again, anytime, to any airline operating this aircraft type.